U.S. patent number 4,238,032 [Application Number 06/062,022] was granted by the patent office on 1980-12-09 for three-position stacking tray.
This patent grant is currently assigned to G. B. Lewis Co.. Invention is credited to Paul G. Thurman.
United States Patent |
4,238,032 |
Thurman |
December 9, 1980 |
Three-position stacking tray
Abstract
A three-position stacking tray having a series of angled ribs on
each side of the tray which comprise the tray's sidewalls. Each
sidewall's ribs are all parallel one to the other, are of identical
structure and size, and are all in a common vertical plane relative
to the floor. The angled ribs of one sidewall are disposed in
mirror relation with the angled ribs of the other sidewall as to
orientation and position. Each rib of each sidewall's angled ribs,
on the same side edges thereof and intermediate the top and bottom
ends thereof, is provided with a notched middle seat adapted to
cooperate with a top seat on an opposite sidewall rib's top end
when the trays are reverse oriented. In the intermediate stack
position, and with upper and lower trays reverse oriented, the top
end seats of the lower tray's angled ribs engage the notched middle
seats defined in the upper tray's angled ribs. Preferably, the
bottom end seats of the upper tray's angled ribs also abut side
edges of the lower tray's angled ribs intermediate the ends
thereof, the upper and lower trays being prevented against motion
in one direction parallel to the sidewalls by engagement of the
upper tray's notched seats and the lower tray's top end seats, and
being prevented against motion in the opposite direction parallel
to the sidewalls by engagement of the upper tray's bottom end seats
and the side edges of the lower tray's angled ribs. To achieve this
intermediate stack position, a vertically in-line but reverse
oriented upper tray is assembled in a vertical downward stroke with
the lower tray.
Inventors: |
Thurman; Paul G. (West Liberty,
OH) |
Assignee: |
G. B. Lewis Co. (Urbana,
OH)
|
Family
ID: |
22039713 |
Appl.
No.: |
06/062,022 |
Filed: |
July 30, 1979 |
Current U.S.
Class: |
206/507; 206/505;
206/518 |
Current CPC
Class: |
B65D
21/041 (20130101) |
Current International
Class: |
B65D
21/04 (20060101); B65D 021/04 () |
Field of
Search: |
;206/505,507,518 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Lowrance; George E.
Attorney, Agent or Firm: Wood, Herron & Evans
Claims
Having described in detail the preferred embodiment of my
invention, what I desire to claim and protect by Letters Patent
is:
1. A three position stacking tray comprising
a floor,
a plurality of angled ribs oriented in a generally vertical plane
on each side of said tray floor for forming opposed side walls on
said tray, each of said angled ribs on each side being parallel to
the other, each of said angled ribs presenting a leading edge and a
trailing edge, and said angled ribs on one side of said tray being
located in mirror relation with said angled ribs on the other side
of said tray,
a top end seat, a middle seat and a bottom end seat, formed on at
least some of said angled ribs on each side of said tray floor,
said rib seats cooperating to permit stacking of identical upper
and lower trays in a nest position one with another by use of a
diagonally downward linear stroke of the upper tray relative to the
lower tray from an offset separated position into an in-line nest
position with said upper and lower tray being like oriented in both
the separated and nest positions, to permit stacking of identical
upper and lower trays in an intermediate stack position one with
another by use of a vertically downward linear stroke of the upper
tray relative to the lower tray from an in-line separated position
to an in-line intermediate stack position with said upper and lower
trays being reverse oriented in both the separated and intermediate
stack positions, and to permit stacking of identical upper and
lower trays in a high stack position one with another by use of a
vertically downward linear stroke of the upper tray relative to the
lower tray from an in-line separated position to an in-line high
stack position with said upper and lower trays being like oriented
in both the separated and high stack position, and
notch structure cut out of a rib between said rib's leading and
trailing edges for defining each middle seat, the notch structure
of an upper tray's ribs being received in seated relation on the
top end seat of a lower tray's ribs to establish said upper and
lower trays in said intermediate stack position, and the upper
tray's bottom end seats being adapted to slide over the lower tray
ribs' trailing edges, and alternatively the upper tray ribs'
leading edges being adapted to slide over the lower tray's top end
seats, in assembly of upper and lower trays in the intermediate
stack position.
2. A three position stacking tray as set forth in claim 1, said
upper tray ribs' bottom end seats cooperating with edges of said
lower tray's ribs to prevent one of forward and rearward motion of
said upper tray relative to said lower tray in said intermediate
stack position, and said upper tray's middle seats cooperating with
said lower tray's top end seats to prevent the other of forward and
rearward motion of said upper tray relative to said lower tray in
said intermediate stack position.
3. A three-position stacking tray as set forth in claim 2, each
notch structure comprising a generally horizontal face and a
generally vertical face, and each top end seat comprising a
generally horizontal face and a generally vertical face, said notch
structure's faces cooperating with said top end seats' faces in the
intermediate stack position.
4. A three-position stacking tray as set forth in claim 3, each
bottom end seat comprising a generally horizontal face and an
angled face, said angled face being angled in a direction opposite
to the angle direction of its associated rib, the angle defined by
said angled rib and the angle defined by said angled face being
substantially equal but oppositely directed.
5. A three-position stacking tray as set forth in claim 4, at least
one of said ribs including a dimple on one of the top and bottom
ends thereof, and an adjacent one of said ribs including a recess
in the other of the top and bottom ends thereof, said dimple and
recess cooperating to prevent at least one forward and rearward
motion of upper and lower trays in the high stack position.
6. A three-position stacking tray as set forth in claim 4, said
tray comprising
a front wall and a rear wall, said walls flaring upwardly and
outwardly relative to said floor.
7. A three-position stacking tray as set forth in claim 6, said
tray further comprising
finger support means disposed along both of said front and rear
walls, thereby permitting said tray to be easily lifted by finger
engagement with said walls.
Description
This invention relates to trays. More particularly this invention
relates to stackable and nestable trays.
Trays of the type that may be stacked on top of one another when
loaded, and that may be nested within one another when empty, are
well known to the prior art. Such trays are commonly used in the
baking industry in transferring of baked goods from one location to
another within the bakery, or in the transporting of baked goods
between the bakery and retail sales outlets, e.g., supermarkets, or
final use locations, e.g., restaurants. Typically, such trays are
used with the transporting or the temporary warehousing of, e.g.,
pies, rolls, and the like.
Many different stackable and nestable tray structures are known to
the prior art as the tray art is a highly developed art. Initially,
trays were developed in which upper and lower trays could be
stacked one upon the other in a use attitude, and nested one within
the other in a storage attitude, only. Such trays are generally
referred to as two-position stacking trays. However, and in recent
years, three-position stacking trays have become known to the tray
art. With the three-position stacking tray, upper and lower trays
are stacked one upon the other in a high stack position when the
trays are loaded with, e.g., a greater height bakery product such
as bread. Upper and lower trays may be further stacked upon one
another in an intermediate stack position when the trays are loaded
with a lesser height bakery product, such as buns. Further, upper
and lower trays may be stacked one upon the other in a low stack or
nest position in a strictly storage attitude when the trays are not
loaded with any product at all, or are loaded with a product having
a low height--less than two inches--such as cakes.
Providing a three position tray design permits the bakery to use
the same trays for differing types of products, and with each
product permits the most efficient utilization of space.
Three position stacking trays are known to the art, as previously
mentioned. Typical of such three-position stacking trays are those
shown in Carroll U.S. Pat. No. 4,102,453, issued July 25, 1978.
This tray and others similar to it have side walls formed in part
by spaced, inclined ribs or bars. In the intermediate and full nest
positions the inclined bars of the upper tray slide diagonally
downward between the bars of the lower tray. The bars must be
provided with shoulders which are engageable to position the trays
in the intermediate position. These trays are not always easy to
locate in the intermediate position because of the need to "find"
the appropriate shoulder as the loaded tray is placed on a similar
tray.
It has been an objective of the present invention to provide a
three position stacking tray in which the trays may be placed, with
relative ease, in any of the three positions, stack, intermediate,
or nest.
It has been a further objective of the invention to provide a three
position stacking tray of the type described in which the product
has a high degree of visibility and ventilation.
The objective of the present invention has been attained by
providing trays having three high side and rear walls and one low
front wall. The two side walls of the tray are formed by inclined
ribs which interconnect upper and lower rails, the upper and lower
rails being spaced apart. The ribs are spaced apart so that an
upper tray can nest into the lower tray by sliding the inclined
ribs of the upper tray into the spaces between the ribs of the
lower tray. Further, the trays can be nested in an intermediate
position by reversing their orientation and simply dropping the
upper tray downwardly into the lower tray with the inclined ribs of
the upper tray being disposed in the space between the ribs of the
lower tray. In the intermediate orientation, the angle of the ribs
is in the direction opposite to that when the trays are fully
nested and therefore the ribs will interfere with one another. It
is the point of the interference which determines how far down in
the lower tray the upper tray can move in order to establish the
intermediate position.
The ribs of the respective trays are provided with notches
intermediate their ends. The notches of the ribs in the upper tray
form seats which receive the upper ends of the ribs in the lower
tray when the trays are nested in the intermediate position. The
notches thus perform several functions, namely, providing a flat
surface for the ribs of the upper tray into the lower tray; and
locking the trays more tightly together.
Other objectives and advantages of this invention will be more
apparent from the following detailed description taken in
conjunction with the drawings in which:
FIG. 1 is a perspective view illustrating a three position stacking
tray structured in accord with the principles of this
invention;
FIG. 2 is a side elevational view of the three position stacking
tray shown in FIG. 1;
FIG. 3 is a rear end view of the three position stacking tray taken
along line 3--3 of FIG. 2;
FIG. 4 is a front end view of the three position stacking tray
taken along line 4--4 of FIG. 2;
FIG. 5 is a cross-sectional view taken along line 5--5 of FIG.
2;
FIG. 6 is a cross-sectional view taken along line 6--6 of FIG.
2;
FIG. 7 is a side cross-sectional view taken along line 7--7 of FIG.
6;
FIG. 8 is a side elevational view illustrating upper and lower
three position nesting trays in accord with the principles of this
invention in an intermediate stack position;
FIG. 9 is a cross-sectional view taken along line 9--9 of FIG.
8;
FIG. 10 is a view similar to FIG. 8 but showing upper and lower
three position nesting trays in accord with the principles of this
invention in a high stack position;
FIG. 11 is a cross-sectional view taken along line 11--11 of FIG.
10;
FIG. 12 is a side elevational view similar to FIGS. 8 and 10 but
showing upper and lower three position nesting trays in accord with
the principles of this invention in a low stack or nest
position;
FIG. 13 is a cross-sectional view taken along line 13--13 of FIG.
12; and
FIG. 14 is a cross-sectional view taken along line 14--14 of FIG.
12.
The three position stacking tray 10 in accord with the principles
of this invention is provided with a low profile front wall 11, a
high profile rear wall 12 and high profile side walls 13, 14. The
side walls 14a, 14b of the tray are disposed in mirror relation one
to the other, i.e., in mirror relation relative to the tray's
median plane 15 which is disposed parallel to and midway between
those side walls, see FIGS. 1, 3 and 4. The tray 10 itself includes
a rectangular floor 16 having side edges 18a, 18b, front edge 19
and rear edge 20. A side wall 14a, 14b structure is connected with
each side edge 18a, 18b, respectively, of the floor, the side walls
14 being outboard of the floor in effect. The front wall 11 is
connected with the floor's front edge 19 and the rear wall 12 is
connected with the tray's rear edge 20. Note the side walls 14a,
14b are in vertical planes 21, 22 relative to horizontal floor 16,
and that the front 11 and rear 12 walls angle upwardly and
outwardly in planes 23, 24 relative to and from horizontal floor
16, see FIGS. 2-4.
Each side wall 14a, 14b structure is comprised of a lower border
flange 30 fixed directly to the floor at its side edge 18, the
lower border flange extending up from the floor 16 to a height H'
no greater than about one-third the total height H of the side wall
14, see FIG. 2. The lower border flange 30 defines an upper edge 31
which is parallel to the tray's floor 16. An upper border flange 32
is located outboard of the lower border flange 30, see FIGS. 1 and
5, and is disposed in parallelism therewith. The upper border
flanges 32 defines an upper edge 33 and a lower edge 34 both of
which also are parallel to the plane of the tray's floor. The upper
border flange 32 is of a height H' also no greater than about
one-third the overall height H of the side wall. The upper 32 and
lower 30 border flanges are separated one from another, and are
held in connected relation one with another between the ends
thereof, by a series of angled ribs or bars 35 of generally
rectangular exterior configuration. The longitudinal axes 36 of the
angled ribs 35 are oriented parallel one to another, and the ribs
are all angled forwardly relative to the tray's low profile front
wall 11, see FIGS. 1 and 2.
The angled ribs 35 of each side wall 14a, 14b each present a
leading edge 37 and a trailing edge 38, and each present a top face
39 and a bottom face 40, see FIGS. 1 and 2. The angled ribs' bottom
faces are horizontal relative to the tray's floor 16, and are
coplanar with lower edge 41 of the tray's lower flange 30. On the
other hand, the angled ribs' top faces 39, while in a common
horizontal plane 42, are positioned somewhat beneath the upper
border flange's upper edge 33, see FIG. 2, thereby defining a gap G
between the upper border flange's upper edge 33 and the horizontal
high stack plane 42 defined by the ribs' top faces 39. Note that
the leading edge 37 of each angled rib 35, at the top end 43 of
each rib, and as particularly shown in FIGS. 1 and 2, is also
provided with a generally vertical face 44 at the top end 43 of
each rib 35, along with the generally horizontal face 39 at the top
end of each rib, cooperate to define a top end seat 39, 44, the
function of which is described in greater detail below. Note
further that the bottom end 45 of each rib 35, on the trailing edge
38 thereof, is provided with an angle face 46 which is angled
rearwardly relative to the front angulation of the angled rib
itself, the angle 47 defined by this rearwardly angulated face 46
being substantially the same, relative to the tray's horizontal
floor 16, as the angle 48 defined by the rib's axis 36 and leading
edge 37 relative to the tray's horizontal floor. This angle face 46
at the bottom end 45 of each rib 35 along with the generally
horizontal face 40 at the bottom end of each rib, cooperated to
define bottom end seat 40, 46, the function of which is described
also in greater detail below. A notch or middle seat 50 is provided
on the leading edge 37 of each angled rib 35 intermediate the top
43 and bottom 45 ends of the rib. The notched 50 is of generally
right angular configuration, and opens forwardly and downwardly
relative to the tray's low profile front wall 11 and floor 16. This
notch 50 is provided with a horizontal face 51 generally coplanar
with top edge 31 of the lower border flange 30, and a vertical
surface 52 which cooperates with the horizontal surface to define
the notch or middle seat. All angle ribs of both side walls 14a,
14b have these structural characteristics except for the forward
rib 55 and rearward rib 56 and most of the angled ribs on each side
wall.
On each side wall 14a, 14b, the forward angle rib 55 is the same as
the intermediate angled ribs 35 except that the top end thereof is
removed due to the upper border flange 32 being connected with the
low profile front wall 11 through a brace member 57 which is, in
effect, an extension of that upper border flange. The brace member
57 defines an upper seat edge 58 and a lower seat edge 59, the
function of which is described in greater detail below. Therefore,
the forward angle rib 55 includes a middle or notch seat 50 in its
leading edge 37 and a bottom end seat 40, 46 at its bottom end 45.
The rearward angle rib 56 of each side wall 14a, 14b includes a top
end 43 similarly configured to the intermediate angled ribs 35, but
the bottom end therefrom is removed due to the intersection of that
rearward rib 56 with the tray's high profile rear wall 12.
Therefore, the rearward angle rib 56 includes a top end seat 39, 44
but no notch seat and no bottom end seat.
Each of the tray's side walls 14a, 14b, therefore is comprised of a
vertical lower border flange 30, and a vertical upper border flange
32 and angled ribs 35, 55, 56 that are oriented in vertical planes
21, 22. The upper 32 and lower 30 border flanges are spaced from
and connected to one another by the angled ribs 35, 55, 56 in that
the inside faces 53 of the angled ribs 35, 55 are fixed to the
lower border flanges's outside face 54, and the outside faces 60 of
the angled ribs 35, 55, 56 are fixed to the upper border flange's
inside face 61. As viewed particularly in FIG. 2, note that the
opposite side walls 14a, 14b structures are oriented in the mirror
relation one with another so that the angle ribs 35, 55, 56 of one
side wall 14a in effect overlie the angle ribs 35, 55, 56 of the
other side wall when the three position nesting tray is viewed in
side elevation as shown. This is an important structural relation
relative to the three-position stack function of the tray' s
structure as described in greater detail below.
The three position stacking tray's rear wall 12 is particularly
shown in FIGS. 1-3 and 7. The rear wall 12, as shown in FIG. 2, is
attached to the rear edge 20 of the tray's floor 16, and slants
upwardly and outwardly relative thereto, i.e., does not extend
vertically upward from the floor's rear edge. The outwardly angled
rear wall 12, at the top edge 62 thereof, is provided with a finger
groove 63 of an inverted channel configuration which allows the
tray's user to pick up the tray by easily gripping it at the rear
wall's top edge. The tray's rear wall 12 extends the width W of the
tray 10, and the lower lip 29 of the top edge 62 is generally
coplanar with the bottom edges 34 of the side walls' upper border
flanges 32. Rear gussets 64 interconnect the upper border flanges
32 on the side walls 14a, 14b with the top edge 62 of the rear wall
12 to reinforce the rear corners of the tray 10. Note each upper
border flange 32, at its rear end 65, defines an angled rear corner
seat 66 having a horizontal edge 67 generally coplanar with the
plantom plane 42 that includes the top end faces 39 of the angled
ribs 35, and a forwardly slanting edge 68 that extends upwardly
from the horizontal edge 67 to the upper border flanges' top edges
33, as shown in FIG. 2, the function of which is described in
detail below.
The tray's low profile front wall 11 is illustrated particularly in
FIGS. 1, 2 and 4, 6 and 7. As shown in those figures, the low
profile front wall 11 is fixed to front edge 19 of the tray's
floor, extends across the width W of the tray from one side wall
14a to the other 14b, and slants upwardly and outwardly relative to
the tray's floor 16, i.e., does not extend vertically upward from
the floor 16. The top edge 70 of this low profile front wall 11 is
provided with a front finger groove 71 of inverted channel shaped
configuration similar to the rear finger groove 63 provided along
the top edge 62 of the tray's rear wall 12. The front 71 and rear
63 ringer grooves cooperate one with another to provide finger
means easily accessible to the tray's user for grabbing hold of and
lifting an upper tray 10 when it is in a nested or stacked
position. The front wall 11 of the tray 10 also defines, at each
front corner thereof, a front pocket 74 in cooperation with the
inverted channel structure that defines the front finger groove 71.
Each pocket 74 is disposed beneath a front corner gusset or latch
plate 75 that aids in reinforcing the front corner of the tray 10
since it is connected both to the tray's front wall 11 and to the
tray's side walls's brace member 57. Note the latch plates 75 and
pockets 74 are each located in a vertical plane 76 normal to the
median plane 15 of the tray 10. The front wall 11 also defines a
seat edge 77 for the bottom edge 78 of the inverted channel shaped
finger groove 71. The front pockets 74 of an upper tray cooperate
with latch plates 75 of a lower tray when two trays are in the
nested position as explained in greater detail below.
Use of the three position stacking tray of this invention is
particularly illustrated in FIGS. 8-12. FIGS. 10 and 11 show upper
10 and lower 10' trays of the same structure in a high stack
position, FIGS. 8 and 9 show upper and lower trays of the same
structure in an intermediate stack position, and FIGS. 12-14 show
upper and lower trays of the same structure in a nest or low stack
position.
In the high stack position shown in FIGS. 10 and 11, upper 10 and
lower 10' trays of identical construction are positioned with their
floors 16 parallel, and in like rotational orientation relative to
each tray's rotation axis 81 (each tray's rotation axis is normal
to the tray's floor 16 and is centered on the floor relative to the
tray's front and rear corners as at point 82). In other words, the
trays are rotationally oriented so that the upper tray's front wall
11 is vertically above the lower tray's front wall, and so that the
upper tray's side walls 14 are oriented above the lower tray's side
walls. In this like rotational orientation for upper 10 and lower
10' trays, and when the trays are vertically spaced or separated
one above the other, the upper tray and lower tray may be high
stacked by a vertically downward stroke of the upper tray onto the
lower tray as illustrated by arrows 83. With the upper 10 and lower
10' trays in like rotational orientation and in a vertical in-line
position (where the tray's axes 81 are coaxial), the upper tray 10
is vertically moved downward toward the stationary lower tray 10'
by vertically downward stroke 83 until the bottom end seat face 40
of the upper tray's angled ribs 35 on the top end seat faces 39 of
the lower tray's angled ribs 35 as shown in FIG. 10. In this high
stack position the upper tray 10 is held in vertical alignment
relative to the lower tray 10', therefore, due to inter-engagement
buttons 86 and dimples 87 in at least one rib per side of the upper
tray angled ribs' bottom end seats 40, 46 and the lower tray angled
ribs' top end seats 39, 44. Side-to-side motion between trays 10,
10' in the direction of arrow 84 is prevented in this high stack
position because the lower ends 45 of the upper tray's angled ribs
35 are recessed beneath the lower tray upper border flanges' top
edges 33, thereby permitting the upper tray angle ribs' bottom ends
45 to be received in a nested relation as shown in FIG. 11. Thus,
the outside faces 60 of the upper tray's angled ribs 35, at the
bottom ends 45 thereof, tends to abut the inside faces 61 of the
lower tray's upper border flanges 32 on each side wall 14a, 14b of
that lower tray 10' to prevent side-to-side motion between trays
10, 10'. Front-to-rear motion between trays 10, 10' in the
direction of phantom arrow 85 is prevented in this high stack
position due to dimples 87 on the bottom faces 40 of the upper
tray's angle ribs 35 receiving buttons 86 in the upper faces of the
lower tray's angle ribs 35. In this regard, and on each side wall
14a, 14b of a tray 10, note the button 86 and dimple 87 are
positioned on adjacent angle ribs 35, see FIG. 2. Removal of the
trays 10, 10' from the high stack position shown in FIG. 10 and 11
is achieved by a vertically upward stroke 88 of the upper tray,
i.e., the reverse of the vertically downward stroke 83.
The intermediate stack position for like structured upper 10 and
lower 10' trays is illustrated in FIGS. 8 and 9. As shown therein,
upper 10 and lower 10' trays are reverse oriented relative one to
another, i.e., relative to the trays' rotation axes 81 with floors
16 parallel. In other words, the trays 10, 10' are rotationally
oriented so that the upper tray's front wall 11 is vertically above
the lower tray's rear wall 12. In this reverse rotation
orientation, and when the trays 10, 10' are vertically spaced or
separated one from the other, the trays may be stacked in
intermediate position by a vertically downward stroke 90 from an
upper in-line position (not shown) to the lower in-line position
shown in FIGS. 8 and 9. In other words, and with the spaced apart
upper tray 10 oriented vertically in line with the lower tray 10'
but reverse oriented from a rotational standpoint, the upper tray
10 need merely be lowered along vertically downward stroke 90 onto
the lower tray until the notched middle seats 50 in the upper
tray's angled ribs 35 are received against the top end seats 39, 44
of the lower tray's angled ribs 35 and until angled rear faces 46
of the upper tray's bottom end seats 40, 46 are seated against the
trailing edges 38 of the lower tray's angled ribs 35 intermediate
the ends thereof, as shown in FIG. 8. Note particularly the space S
available to compensate for user error as to vertical in-line
positions of upper 10 and lower 10' trays in the event the trays
are not perfectly vertically aligned before the vertically downward
stroke 90. In this regard, initial contact of the upper trays
angled faces 46 anywhere along the upper length L of the trailing
edges 38 of the lower tray's angled ribs 35 will allow the upper
tray 10 to slide into the intermediate stack position front to rear
motion (indicated by arrows 91, 92) of the upper tray 10 relative
to thw lower tray 10' is prevented by the structural seat relation
that retains the upper tray in vertical or intermediate stack
position with the lower tray. In this regard, the upper tray's
notches 50 cooperate with the top ends 43 of the lower tray's
angled bars 35 to prevent motion of the upper tray 10 in the
rearward direction 91 relative to the lower tray 10', and the
bottom end seats 40, 46 of the upper tray's angled ribs 35
cooperate with or abut against the trailing edges 38 of the lower
tray's angled ribs 35 to prevent motion of the upper tray in the
forward direction 92 relative to the lower tray. Side-to-side
motion 96 is prevented between upper tray 10a and lower tray 10'
because the outside faces 60 of the upper tray's angled ribs 35
tend to butt against the inside faces 61 of the lower tray's upper
border flanges 32, see FIG. 9. This prevents side-to-side motion 96
of the upper tray relative to the lower tray. Note also in the
intermediate stack position, when the upper 10 and lower 10' trays
are reverse oriented relative one to another, that corner brace
members 57 of the upper tray are seated in rear corner seats 66 of
the lower tray's upper border flanges 32 to accommodate the
intermediate stack position. Removal of the trays 10, 10' from the
intermediate stack position is achieved by vertically lifting,
along a reverse vertical path shown by phantom arrow 99, the upper
tray 10 until it is separated from the lower tray 10'.
The third position of the upper 10 and lower 10' three position
stacking trays is the low stack or nest position illustrated in
FIGS. 12-14. To achieve this nest position, the upper tray 10 must
be like oriented on rotational axis 81 relative to the lower tray
10', but located in a forwardly offset position (not shown)
relative to the lower tray when elevated above it and prior to
nesting within it. In this regard, the upper tray 10 is moved
forwardly or separated until the axes 36 of its side walls' angled
ribs 35 are located parallel and midway between adjacent like
positioned bars 35 of the lower tray's side walls 14a, 14b, see
phantom axis 101 line of an upper tray's angled rib 35 when in the
offset position prior to nesting with the lower tray 10'. When the
upper tray 10 is in the elevated but forwardly offset position (not
shown), nesting of the upper tray with the stationary lower tray
10' is achieved by a diagonally downward and rearward stroke
illustrated by phantom arrow 102 from the offset position to a
vertically in-line position shown in FIG. 12. When nesting upper
tray 10 with lower tray 10', it is not necessary that the upper
tray ribs's axes 101 be exactly aligned between the leading 37 and
trailing 38 edges of adjacent ribs 35 of the lower tray 10' prior
to and/or during the diagonally downward nesting stroke 102. It is
only necessary that the bottom ends 45 of the leading edges 37 of
the upper tray's ribs 35 engage the top ends 43 of the trailing
edges 38 of the lower tray's ribs 35, the upper tray's ribs'
leading edges 37 then sliding down over the lower tray's ribs'
trailing edges 38 until the nested position is achieved. Thus, and
in both the intermediate stack and nest positions, the trailing
edges 38 of the lower tray's ribs 35 act as slideways for the upper
tray's ribs 35 to aid in achieving the desired position. In the
intermediate stack position the lower trays ribs' trailing edges 38
cooperate with the upper tray ribs' rear surface 46, and in the
nest position the lower tray ribs' trailing edges 38 may cooperate
with the upper tray ribs' trailing edges 37, to guide the upper
tray 10 into the desired position with the lower tray 10'. Further,
in the intermediate stack position the leading edges 37 of the
upper tray's ribs 35 may act as slideways to aid in achieving the
desired position. In this latter situation, the upper tray ribs'
leading edges 37 may slide over the point defined by surfaces 39,
44 of the lower tray angled ribs' top end seats 43 to guide the
upper tray 10 into the intermediate stack position with the lower
tray 10'.
When the upper tray 10 is fully nested within the lower tray 10',
the nesting position is vertically established by interengagement
of the lower edges 34 of the upper tray's border flanges 32 with
the upper edges 33 of the lower tray's upper border flanges 32, see
FIGS. 12 and 13. In this fully nested position, side-to-side motion
of the upper tray 10 relative to the lower tray 10', shown by
phantom arrow 103, is prevented due to the fact that the outside
faces 60 of the upper tray's angled ribs 35 are received
immediately within the inside faces 61 of the lower tray's upper
border flanges 32, thereby preventing side-to-side motion as shown
in FIG. 13. Rearward motion of the upper tray 10 relative to the
lower tray 10' in the nest position, as shown by arrow 104 in FIG.
12, is prevented due to the telescoping or nesting position of the
upper tray's rear wall 12 within the lower tray's rear wall 12 as
at 105. Forward motion of the upper tray 10 relative to the lower
tray 10' in the nest position, as shown by arrow 106, is prevented
due to contact as at 107 between the leading edges 37 of the upper
tray's angled ribs 35 with the trailing edges 38 of the lower
tray's angled ribs 35. Further, forward 106 and rearward 104 motion
of the upper tray 10 relative to the lower tray 10' is prevented in
the nested position due to receipt of the lower tray's latch plates
75 at each front corner thereof in latch plate pockets 74 defined
in the front corners of the upper tray 10, see FIG. 14. Note also
that, when the upper 10 and lower 10' trays are in nested position,
the brace members 57 at the front corners of the upper tray are
received in seated relation with seats 58 defined by the brace
member 57 at the front corners of the lower tray. Further, the
bottom edge 78 of the upper trays's front finger groove 71 seats on
seat edge 77 of the lower tray 10 at each front corner when the
trays are nested. This tends to reinforce the front corners of the
trays when the trays are nested due to the low profile nature of
their front walls 11.
* * * * *